Lump on lemon tetra’s side

[FishFriend0]

For the past few weeks one of my lemon tetras has had a lump on it’s side which has gotten bigger. It doesn’t seem to impacted behaviourally but I was just concerned what it could be. It looks like some sort of tumor to me but what do you make of it?

 

[Colin_T]

It could be a parasitic worm that got lost in the fish. Praziquantel or Flubendazole would kill the worm but it will remain in the body.

 

[GaryE]

It can be a cyst as well. Sometimes, that's a disease encysted, sometimes not. A tumour isn't likely, but possible. As Colin says, it can be a parasite.
When it comes to wanting certainty, fish medicine isn't where you want to go. All we can usually do is watch and see what happens.

 

[FishFriend0]

Ok, I will keep an eye on it over the next couple of days. Thanks guys